The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 26, 2005
Filed:
Jun. 19, 2002
Koichi Yoshiki, Saitama-ken, JP;
Yukio Miyashita, Saitama-ken, JP;
Hideyuki Oki, Saitama-ken, JP;
Takashi Isobe, Saitama-ken, JP;
Tetsuya Ohno, Saitama-ken, JP;
Kojiro Tsutsumi, Saitama-ken, JP;
Koichi Yoshiki, Saitama-ken, JP;
Yukio Miyashita, Saitama-ken, JP;
Hideyuki Oki, Saitama-ken, JP;
Takashi Isobe, Saitama-ken, JP;
Tetsuya Ohno, Saitama-ken, JP;
Kojiro Tsutsumi, Saitama-ken, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A fault determining apparatus for a variable valve timing mechanism is provided for shortly and accurately determining a fault even at low oil temperatures. The mechanism is driven by an oil pressure to change a cam phase of an intake cam and/or an exhaust cam with respect to a crank shaft of an internal combustion engine, thereby controlling the actual cam phase to reach a target cam phase. The apparatus has a fault determining routine executed by an ECU (electric control unit) for determining that the mechanism is faulty when a cam phase difference between the target cam phase and the actual cam phase is not within a predetermined range, an oil temperature sensor for detecting the temperature of the working oil, and a correcting routine executed by the ECU for correcting the predetermined range in an increasing direction when the detected oil temperature is low.